This invention relates to surgical tables and more particularly, to an improved radiolucent table extension and radiolucent adaptor assembly which facilitates interoperative scanning.
With current medical practices, it is common for a patient to undergo a diagnostic scanning procedure, which is normally performed in a separate suite containing the scanning machine and dedicated to scanning procedures. The scanning machine may be a CT, MRI, or other scanning device. Thereafter, the scan data is utilized in a surgical planning process, which conventionally takes place at a location, for example, an office or an operating room. In some surgical procedures, the scanning data is utilized with a system for post processing the scan data acquired during imaging. Further, the imaging system may be located in a surgical suite, and the surgical planning performed before and during surgical procedure utilizing the imaging system and scan data.
During the scanning procedure, the patient must maintain a perfectly still and motionless posture, and while most often, the patient simply lies on a scanning support table, in some situations, the patient maybe supported in the desired scanning position with pads, straps or other supports. Further, the support on which the patient rests is normally radiolucent, that is, transparent to the scanning device, so that the support does not compromise the utility of the scanned image. Further, the patient support used for scanning normally translates with respect to the imaging device. Translation of the patient support permits the patient to be moved into the scanning field or zone of the scanning machine.
After the scanning process is completed, often the patient is then moved to an operating room which requires either that the patient walk, or be carried, for example, by transferring the patient from the scanning table to an operating table. Alternatively, as illustrated in U.S. Pat. No. 5,475,884, the patient may be supported on a portable support plate, which is easily moved between the scanning table and the operating table. The scan data is often used in a post processing imaging system for surgical planning purposes both prior to and during surgery. If during or after a surgical process, it is desired to scan a patient again, the patient must be moved from the operating room to the scanning suite, transferred to and from the operating table to the scanning table, and after scanning, transferred back to the operating table and returned to the operating room. The above process is cumbersome, time consuming and potentially risky for the patient.
Some newer scanning machines are substantially reduced in size. One such machine is shown in FIGS. 2 and 3 of U.S. Pat. No. 5,499,415, which show an annular-shaped scanner mounted on a wheel-supported frame, to enable the scanner to be used at multiple sites. Consequently, such scanning machines do not require their own suite or room, but instead, they may be used within the operating suite itself. Thus, in an operating room, the patient may be scanned; the surgical planning performed; an operative procedure executed; and the patient scanned again to determine the current status of the operative procedure. Based on the new scanned images obtained from the one or more xe2x80x9cinteroperativexe2x80x9d scans, the operative procedure can be continued and the above process repeated as necessary.
A limitation of the current state-of-the-art is that the posture of the patient during the scanning process is often different from the patient""s posture during surgery. If a patient is positioned in one posture on a scanning table during the scanning process, and then is moved to an operating table, that motion of the patient may cause the position of the target to change with respect to the body surface. During surgery, this problem is compounded by tissue shifts attendant to the opening of body cavities, removal of body fluid or tissues and tissue retractions. Thus, while such motion may be small, any motion of the target will reduce or compromise the utility of the preoperative scan data.
The solution to these problems is to scan the patient in the operating room during surgery while the patient is maintained in the surgical posture, and further, to make successive interoperative scans, as necessary, while still holding the patient in the same surgical posture.
While current scanning tables are radiolucent and provide a translation to move the patient into the scanning machine, such scanning tables do not have the accessories required to attach, support and stabilize surgical instrumentation and to properly support the patient""s body in the desired surgical posture. Further, while surgical, or operating tables contain numerous accessories and couplings to which surgical instrumentation may be attached and supported, most operating tables are not compatible with scanning instrumentation. Thus, as presently known, scanning tables cannot be used as operating tables, and generally, operating tables are inappropriate for use as scanning tables.
It is an object of this invention to overcome the above-described limitations in the prior art, by facilitating the function of supporting a patient in a desired position in a manner which readily accommodates successive surgical or scanning procedures.
It is another object of the invention to optimize versatility in the supporting of a patient in a desired position which accommodates interoperative scans.
The present invention achieves the above-stated objectives with a radiolucent table extension that connects to a surgical table and permits a patient to be positioned on the table in a posture suitable for successive surgical or scanning procedures, the head and the upper torso of the patient supported on the table extension, a radiolucent adaptor assembly hingedly connected to the radiolucent table extension and a radiolucent support, of a type which holds either a radiolucent horseshoe headrest or a radiolucent skull clamp, hingedly connected to the radiolucent adaptor assembly. The present invention represents an improvement in versatility over the structure shown and described in U.S. patent application Ser. No. 08/922,969, entitled xe2x80x9cRadiolucent Table Extension and Method,xe2x80x9d which is expressly incorporated by reference herein, in its entirety.
The radiolucent table extension is cantilevered from one end of the surgical table and it is shaped so that it may be moved in a relative manner into a toroidal shaped scanning zone of an upright annular scanning machine. This permits the patient to be scanned in the desired surgical posture. The radiolucent table extension and the radiolucent adaptor assembly of this invention are especially useful for those procedures in which it is desirable to maintain the patient in a desired position during successive scanning or surgical procedures.
By operatively connecting the toroidal scanner to an imaging system, so that the imaging system may store data representative of scans of the patient taken in the scanning zone, and by supporting the patient with the extension and the hingedly connected adaptor, and fixing the position of the patient with the horseshoe headrest or the skull clamp hingedly connected to the adaptor, the present invention optimizes versatility in the positioning of a patient during successive scans, thereby assuring the accuracy of the scanned data. This helps the surgeon to know almost immediately whether the surgical procedure accomplished its objective, or whether continutation of the surgical procedure may be necessary.
According to the principles of the present invention and in accordance with the preferred embodiments, a radiolucent table extension has a first inboard end adapted to be attached to one end of a surgical table. The table extension includes a contoured radiolucent member designed to support an upper torso and head of a patient with the rest of the patient""s body being further supported by an adjacently located surface of the table. The member has a sufficiently narrow width to permit it to be extended, in cantilever fashion, into a scanning zone of portable CT scanning system. A second, or outboard end of the radiolucent table extension hingedly connects to a radiolucent adaptor assembly, which preferably comprises two spaced radiolucent adaptor subassemblies hingedly connected along a first connection axis to spaced collars located at the outboard end of the radiolucent member. An arcuate cutout resides between the two spaced collars. This cutout advantageously defines an opening between the extension and the radiolucent support to accommodate surgical tubing. Likewise, a radiolucent support also has two spaced collars aligned along a second connection axis, and the radiolucent support hingedly connects to the radiolucent adaptor assembly along a second connection axis. The two connection axes are parallel, and if desired they may reside in the same vertical plane. The radiolucent support is adapted to support at least one cranial stabilization device, typically either a radiolucent skull clamp or a radiolucent horseshoe headrest.
The radiolucent adaptor assembly actually comprises two spaced adaptor subassemblies. Each radiolucent adaptor subassembly includes opposing interior and exterior pieces which are tightenable, via a threaded adjustment knob, into rigid engagement with the spaced table extension collars and the spaced support collars. Each of the interior and exterior pieces has locator pins in alignment with the first and second connection axes. Along each connection axis, the locator pins extend into the respective collar with a slip fit. The locator pins provide the hinged connection between the radiolucent table extension and the radiolucent adaptor along the first connection axis and the hinged connection between the radiolucent support and the radiolucent adaptor along the second connection axis. Tightening of the adjustment knob effectively moves the interior and exterior pieces horizontally toward each other to engage the outer ends of the collars, preferably via corresponding serrated, or starburst surfaces, thereby to achieve rigid holding. Thus, even though there is hinged capability along two spaced axes, the radiolucent support is locked in place via actuation of knobs residing on a single axis.
The hingedly connected radiolucent support is adapted to support at least one patient stabilization device, typically either a radiolucent skull clamp or a radiolucent horseshoe headrest. When using a radiolucent skull clamp, the radiolucent support comprises a radiolucent bracket which supports a ninety degree radiolucent intermediate connector which in turn holds the radiolucent skull clamp. The radiolucent bracket and the radiolucent intermediate connector connect along a dovetail slot, to enable the radiolucent skull clamp to be slidably located at a desired position relative to the longitudinal axis of the table extension, as may be desired in certain situations.
When the patient stabilization device is a horseshoe headrest, the radiolucent support is a U-shaped panel bearing an upstanding slide mount oriented transverse to the longitudinal direction of the table extension. The radiolucent horseshoe headrest comprises two separate arcuate halves which slidably attach to the slide mount, to form a U-shape for holding the head of the patient.
The U-shaped panel combines with the arcuate cutout region at the outboard end of the table extension to form an enclosed oval, which is advantageous for certain procedures wherein the patient must be positioned face down. In this arrangement the radiolucent adaptor assembly represents, in effect, an intermediately located, double hinge for the entire support assembly attached in cantilever fashion to the surgical table.
Because of the configuration of the radiolucent adaptor assembly, and the configuration of the two different radiolucent supports for holding either a skull clamp or a horseshoe headrest, the present invention provides rigid connection of either configuration with the same adaptor assembly. Thus, the invention greatly simplifies and shortens the time needed for surgical attendants to interchange between a skull clamp set up and a horseshoe headrest set up. Even with a high degree of rigidity and with this ability to easily interchange between two different patient stabilization devices, the present invention also achieves enhanced maneuverability of the patient stabilization device, due to the two hinged connections. According to another aspect of the invention, the adaptor assembly accommodates connection of a horseshoe headrest in an inboard manner, partially surrounding an enclosed oval. The headrest is inboard because the radiolucent plate holding the headrest represents an outermost end of the entire cantilevered structure, and the two hingeable axes reside between this outermost end and the table extension.
Thus, the double-hinged radiolucent adaptor assembly of the present invention optimizes versatility in supportably positioning a patient on a radiolucent table extension, via either a radiolucent skull clamp or a radiolucent horseshoe headrest. With this inventive structure, the patient can be supported on the radiolucent table extension in the desired posture. The patient can then be conveniently scanned before a surgical procedure. After surgery, a subsequent scanning procedures may be performed, if necessary or if desired. Thus, the table extension and adaptor assembly have the advantage of not requiring that the patient be moved with respect to the table extension between successive scanning and surgical procedures.
Moreover with updated scanned images readily available for viewing via the imaging system, the surgeon can review the results of a surgical procedure to determine if a particular operation has been completely successful. For example, if the objective of the surgery was to completely remove a hematoma from the brain, a follow-up scan may enable the surgeon to use the imaging system to determine if the entire hematoma has been removed. If a subsequent scan shows that some of the xe2x80x9ctargetxe2x80x9d remains, then the surgeon can continue the surgical procedure, using the imaging system if desired, to achieve 100% removal of the target. Thus, this overall system facilitates successive scanning and surgical procedures, and the radiolucent table extension and the radiolucent adaptor assembly make it possible to use this system more effectively, by assuring accurate and repeatable positioning of the patient.
These and other objects and advantages of the present invention will become more readily apparent from the following detailed description and the drawings.